Paris - Researchers unveiled a high-resolution “map” on Wednesday of gene activity in a human foetus brain, which they said should lead to better understanding of developmental disorders such as autism.
The blueprint, compiled with the donated brain tissue of four foetuses 15 to 21 weeks post conception, shows which of some 20 000 genes are active in any given area of the brain at different periods of development.
This age, “from a developmental biology point of view, this is really when we are setting up the whole system and in particular... when we are beginning to establish the neocortex which is responsible for many of our most distinctive cognitive processes,” said project member Ed Lein of the Allen Institue for Brain Sciences in Seattle.
“So by studying this early period of time we can really understand how genes drive the generation of many different type of neurons that ultimately form our functional circuits,” he said in a podcast distributed by Nature, which published the study.
The institute had previously built maps for mouse and adult human brains.
The new resource, known as the BrainSpan Atlas of the Developing Human Brian, is available to researchers for free.
Lein said one study using the map looked at genes associated with autism, and found a specific area of the brain where they were most active during a specific period of development.
“This of course does not really tell us a mechanism but it tells us where we perhaps should look, and in this particular case, really points sort of to the idea that some of the roots of autism may be in this particular process happening prenatally,” he said.
It is hoped similar patterns can be found for other disorders at this early developmental phase.
“This is the beginning,” said Lein.
“Really we want to understand the blueprint whereby we build a brain, and this is sort of one step in that direction whereby we can begin to have a map of how genes are driving this process.”
A separate study in Nature presented a map of neuron wiring of the mouse brain, described as “the most comprehensive to date in any vertebrate species”.
“The authors suggest that the data generated here may assist investigations of neural networks in humans, which could help to further our understanding of human brain connectivity and its involvement in brain disorders,” said a press summary. - Sapa-AFP